(3-Aminophenyl)methanol

In the title compound, C7H9NO, a derivative of benzyl alcohol, the endocyclic C—C—C angles are in the range 119.50 (12)–121.04 (12)°. In the crystal, molecules are linked by N—H⋯O hydrogen-bond interactions, forming an extended two-dimensional framework parallel to ab. O—H⋯N interactions are also observed.


Comment
Chelate ligands have found widespread use in coordination chemistry due to the enhanced thermodynamic stability of resultant coordination compounds in relation to coordination compounds exclusively applying comparable monodentate ligands (Gade, 1998). Combining two different donor atoms, a molecular set-up to accomodate a large variety of metal centers of variable Lewis acidity is at hand. In this aspect, 3-aminobenzyl alcohol seemed of interest due to its possible use as a strictly neutral or, depending on the pH value, as an anionic or cationic ligand. In addition, due to the set-up of its functional groups, it may act as mono-or bidentate ligand offering the possibility to create seven-membered chelate rings. To enable comparative studies in terms of bond lengths and angles in envisioned coordination compounds, we determined the molecular and crystal structure of the title compound. Information about the crystal structure of (3-(Hydroxymethyl)phenyl)bis(diphenylphosphinomethyl)amine (Hursthouse et al., 2003) as well as 3-nitrobenzyl alcohol as a co-crystallizate with platinum-containing coordination compounds (Oskui et al., 1999) is available in the literature.
The hydroxymethyl group is not in plane with the aromatic system, the respective dihedral angle was found at 33.0 (2) °.
The biggest angle is found on the C atom bearing the amino group (Fig. 1).
In the crystal structure, a cooperative set of hydrogen bonds involving all nitrogen-and oxygen-bonded hydrogen atoms is present. While the oxygen atom acts as twofold acceptor for hydrogen bonds exclusively stemming from the H atoms of the amino group, the nitrogen atom of the amino group serves as acceptor for a hydrogen bond originating from the hydroxyl group's O atom. In terms of graph-set analysis (Etter et al., 1990;Bernstein et al., 1995), the descriptor for this hydrogen bonding system on the unitary level is C 1 1 (7)C 1 1 (7)C 1 1 (7). In the crystal the molecules are linked by N-H···O hydrogen-bond interactions, forming an extended two-dimensional framework parallel to the ab, Fig. 2. π-Stacking is not a prominent feature of the crystal structure with the shortest intercentroid distance between two aromatic systems measured at 5.5741 (10) Å . (Fig. 2).

Experimental
The compound was obtained commercially (Aldrich). Crystals suitable for the X-ray diffraction study were obtained upon free evaporation of a solution of the compound in acetonitrile at room temperature.

Refinement
Carbon-bound H atoms were placed in calculated positions (C-H 0.99-0.95 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2U eq (C). The hydrogen atoms of the hydroxyl group as well as of the amino group were located on a difference Fourier map and refined freely.  Fig. 1. The molecular structure of the title compound, with atom labels and anisotropic displacement ellipsoids (drawn at 50% probability level). 1, y -1, z; iii -x + 1, y -1/2, -z + 1/2; iv -x + 1, y + 1/2, -z + 1/2; v x, y + 1, z; vi x + 1, y + 1, z.